I have to decide wether to either just get new 18650′s (Xtar 18700′s ) for
my Fenix TK35 and a charger for them, or to get what i just mentioned, and
a Xtar TZ20. But what i really would want, is a Olight M20X but if i got
that, i would have spent $450 on flashlights in the last 2 months! (Sweden
and its high sale tax :C, only my TK35 was $160) Flashlights make me go
sleepless sometimes -.-

I see. On my lacrosse charger it charges at either 200ma, 500, or 700. The
700 charges aa’s in a few hours but they get pretty hot. About what speed
does that cool Nitecore charger charge at would you say? Is it more of a
longer 12-16 hour charger or does it seem to charge faster?

The 3400 are about 10% higher capacity, but are also a little bit longer,
so they might not fit in your light. You don’t want to mix battery types in
the same light. The Nitecore would take about the same amount of time if
you had all four batteries in there at once.

Eagletac is manufacturing them on a much larger scale and can handle a
whole lot more since they have a large dealer network. AW is kind of a
small niche manufacturer. They use the same cells in the 3100s. I’m not
smart enough to know the differences in the circuits, but I’ve had great
luck with the Eagletacs.

With that Nitecore charger can you select the voltage — how fast– it
charges the batteries? I can do that with my LaCrosse charger, but that
Nitecore one is intriguing because it can do Li Ion batteries too as you
said. I might look into that.